PHOTOS: Zoo Panda Cub Died From Liver Necrosis

WASHINGTON (WUSA) -- National Zoo officials shared the results of the panda cub necropsy on Thursday morning. According to officials, the cub had lung and liver damage, and died from liver necrosis.

The cub was born on Sunday, Sept. 16 and died several days later. Officials say that the cub weighted less than 100 grams (or about 4 ounces) at birth.

According to officials, the cub's lungs were not fully formed and the cell death in the liver of the cub indicates there was not enough oxygen getting to the liver.

Later in September, officials with the Smithsonian National Zoo shared preliminary results from the necropsy of the giant panda cub.Chief veterinarian Dr. Suzan Murray shared the following:

there was evidence of milk in the cub's gastrointestinal tract, meaning the cub had been nursed, but they don't know at this point how recently it had been nursed

free fluid was discovered in the abdomen. The amount was moderate to increased for a cub but further testing will determine more about whether this was a factor in the death

the cub's liver felt hard in places and the color was not uniform, indicating that the liver may be a component ion the death but again, officials won't know until the slides are back

the coat of the cub was in good condition

officials say the cub may have been a female

Zoo officials said in a press release that "The mortality rate for pandas in their first year of age in human care is 26 percent for males and 20 percent for females."

Thursday, officials said that Mei Xiang, the cub's mother, has mostly returned to normal behavior. National Zoo officials and their Chinese counterparts have not yet made a decision about the future of Mei Xiang and Tian Tian, the cub's father, at the National Zoo. The two countries have an agreement through December 2015 concerning breeding and cub behavior research. Officials said on Thursday morning that they will be meeting later in the fall to discuss whether the two pandas will stay at the zoo. There is the possibility that the zoo could exchange one or both of them with China.